David J. Mabberley

Background: Orange jasmine has a complex nomenclatural history and is now known asMurraya paniculata(L.) Jack. Our interest in this common ornamental stemmed from the need to resolve its identity and the identities of closely related taxa as hosts of the pathogen ‘CandidatusLiberibacter asiaticus’ and its vectorDiaphorina citri. Understanding these microbe-vector-plant relationships has been hampered by taxonomic confusion surroundingMurrayaat both the generic and specific levels.Results: To resolve the taxonomic uncertainty, six regions of the maternally-inherited chloroplastal genome and part of the nuclear-encoded ITS region were amplified from 85 accessions ofMurrayaandMerrilliausing the polymerase chain reaction (PCR). Clustering used maximum parsimony (MP), maximum likelihood (ML) and Bayesian inference (BI). Chronograms were produced for molecular dating, and to test the monophyly ofMurrayarigorously, using selected accessions ofMurrayaand 26 accessions of the Rutaceae and Simarubaceae. Sequence data from the ITS and chloroplastal regions suggest thatMurraya paniculata(sensu (Swingle WT and Reece CR, The Citrus Industry, p. 190–430, 1967)) can be separated into four distinct but morphologically somewhat cryptic taxa:Murraya paniculata(sensu (Mabberley DJ, Taxon 65:366–371, 2016)),M. elongata,M. sumatranaandM. lucida. In addition,Murraya omphalocarpawas identified as a putative hybrid ofM. paniculataandM. lucidawith two geographically isolated nothovarieties representing reciprocal crosses.Murrayais monophyletic, and molecular dating suggests that it diverged fromMerrilliaduring the Miocene (23–5 Ma) with thisMurrayagroup speciating and dispersing during the Middle Miocene onwards.Conclusions: The accessions from Asia and Australasia used in this study grouped into biogeographical regions that match herbarium specimen records for the taxa that suggest natural allopatric distributions with limited overlap and hybridity.Murraya paniculatahas been distributed around the world as an ornamental plant. The division of theMurraya paniculatacomplex into four species with a rare hybrid also confirms morphological studies.

Investigation of the provenance of a herbarium gathering of Kissenia arabica (Loasaceae) at the Natural History Museum, London, reveals it to be part of the likely earliest extant herbarium collection from the south Arabian coast. Gathered in 1781–1782, the collection was possibly made by the colourful John Oswald (c. 1760–1793).

A consideration of the naming of Hibiscus patersonius (Malvaceae) and similar names leads to the conclusion that such adjectival forms in specific epithets are in accordance with Classical Latin and that their “correction” to other adjectival forms or the genitive form of nouns is disruptive in botanical Latin.

The discovery, introduction and naming of the chestnut vine (Tetrastigma voinierianum, Vitaceae), a Vietnamese plant, is examined and bibliographic citation corrected. The 173 at the time of writing disregarded new species names and new combinations made in Séraphin Mottet’s Dictionnaire Pratique d’Horticulture et Jardinage (1892–1899) include six names in current use, hitherto attributed to later authors. All the other Mottet novelties, as well as the 125 disregarded in Nicholson’s ‘mother volume’, his Illustrated Dictionary of Gardening (four names in current use) and its later Century Supplement (22) have been passed to IPNI editors as have 15 from Bois’s Dictionnaire d’Horticulture Illustré: none disturbs current nomenclature save six changes in authority. Many species introduced to cultivation by Veitch were much cited by Mottet and Nicholson but were first published in Veitch catalogues, necessitating a new name in Miconia (Melastomataceae) and seven changes in authority in names in current use.